Measuring 0-60 Performance on iPhone?

[Agon]

1) Open the browser in the car
2) Find a webpage with a stop watch
3) Start the stop watch in the browser
4) Record a video with your phone with speedometer and stopwatch in one picture and accelerate from 0 and past 60
5) Review your video and note time when speedometer leaves zero and when it passes 60 mph and subtract.

It works quite well

 

[1.21GW]

1) Open the browser in the car
2) Find a webpage with a stop watch
3) Start the stop watch in the browser
4) Record a video with your phone with speedometer and stopwatch in one picture and accelerate from 0 and past 60
5) Review your video and note time when speedometer leaves zero and when it passes 60 mph and subtract.

It works quite well

The challenge with using all of these different methods is understanding the gage R&R and also your Measurement System Analysis (MSA)